TORONTO — Chris Sale, his counterpart, stood six-foot-six on the mound, with a wingspan that was reportedly 81 inches across. The Chicago White Sox pitcher was a sinewy collection of grey pant legs and comic book arms; the left arm seeming to sweep half the infield for each delivery.

Marcus Stroman was none of that. He was a right-hander, and a notably shorter pitcher at that. A compact five-foot-nine, he also began the season much deeper on the depth chart, not as an ace, like Sale, but as a prospect with the Toronto Blue Jays.

On Saturday afternoon, though, the prospect outduelled the ace. Stroman had the lead and edge in the pitching line when he left in the seventh inning. The bullpen denied him a win, though, and left the Blue Jays on the wrong end of a 4-3 final at home .

“He threw better than I did,” Sale told reporters.

Stroman struck out six and allowed only two runs in 6 2/3 innings of work against the White Sox, the last-place team in the AL Central. Both runs were earned, but crossed the plate at the end of a home run hit after he had left the game.

Dustin McGowan had been called on in relief. His very first pitch was hammered into the second deck at Rogers Centre by White Sox outfielder Dayan Viciedo. That undid all the work Stroman completed before manager John Gibbons opted to make the change.

Marcus Stroman #54 of the Toronto Blue Jays delivers a pitch in the first inning during MLB game action against the Chicago White Sox on June 28, 2014 at Rogers Centre in Toronto, Ontario, Canada. (Photo by Tom Szczerbowski/Getty Images)

“Yeah, it’s tough, because obviously I want to be out there,” Stroman said. “But I’m also a young guy, so that was Gibby’s choice. And Dustin’s been great for us all year, so it’s not like I was mad about coming out of the game. I had 100 per cent confidence for Dustin to come in and get that out — so it’s just one of those things.”

Toronto was without two of its most important bats for the sixth game in a row. Slugger Jose Bautista was taking another day to rest a strained hamstring, with no clear timetable set for his return. Brett Lawrie (broken finger) remained on the disabled list.

The Blue Jays delivered their only run support for Stroman in the fourth inning. It came off the bat of the man playing right field for the injured Bautista, with Darin Mastroianni starting only hours after being recalled from Triple-A Buffalo.

Mastroianni, a right-handed batter, like Bautista, had started the year 0-for-14 at the big-league plate. With Colby Rasmus on base after a walk, the 28-year-old replacement drove Sale over the wall in centre-field for a 2-0 lead.

Toronto Blue Jays relief pitcher Dustin McGowan, left, walks off the mound as Chicago White Sox’s Dayan Viciedo rounds the bases following a three-run home run in the seventh inning of MLB baseball action in Toronto on Saturday, June 28, 2014. (THE CANADIAN PRESS/Darren Calabrese)

Stroman stumbled on his next trip back to the mound. He walked Adam Dunn — having fallen behind 3-0 in the count — and after striking Viciedo out, he fell behind 3-1 against Alejandro De Aza. Stroman rallied for the strikeout, and escaped cleanly after Dunn was caught in a rundown between first and second.

“I mean, he’s a short guy,” Gibbons had said of his starter. “But when he walks around, he’s 10 feet tall.”

Stroman was only making the sixth start of his major-league career. He earned his first win as a starter on May 31, and had shown some resilience in the following four games. He was pulled in the fourth inning of a start against the New York Yankees — after allowing two runs off four hits — but rallied to eight innings deep for a win over the Yankees in his next start.

On Saturday, Gibbons called for relief after Stroman walked Dunn again, after conceding a double to Jose Abreu. There were two outs, but Gibbons had apparently seen enough.

Munenori Kawasaki #66 of the Toronto Blue Jays grounds out in the fourth inning during MLB game action against the Chicago White Sox on June 28, 2014 at Rogers Centre in Toronto, Ontario, Canada. (Photo by Tom Szczerbowski/Getty Images)

The crowd, announced as 39,623 under a flawless summer afternoon, rose to its feet to applaud Stroman as he walked to the dugout. When McGowan followed a few minutes later, after ruining Stroman’s good work with the home run, the crowd booed.

McGowan allowed three hits and two earned runs in one inning of work. The White Sox scored another run in the eighth inning with Aaron Loup on the mound.

Sale conceded the mound after seven, leaving the game with four hits, five walks, six strikeouts and a pair of earned runs . Stroman also struck out six and walked only two before his manager judged him to be spent.

“My thinking was, he pitched his butt off (and he’s in) kind of uncharted territory,” Gibbons said. “I had a plan and it just didn’t work.”

He paused a beat before continuing.

“I’m sure you’ll highlight the next time, (when) that plan works,” Gibbons said with a sly grin. “Like you always do.”